m-PEG12-CH2CH2NHCH2CH2COOH linker contains a secondary amine along the spacer and a terminal carboxylic acid. The secondary amine on the spacer can react with activated carboxylic acid ester modified biomolecules. The terminal carboxylic acid readily reacts with primary and secondary amine under EDC, DCC, HATU or other amide coupling conditions to form a stable amide bond. The mPEG modification increases the aqueous solubility of the resulting compound.
AxisPharm offers 5000+ PEG Linkers with high purity. Different kinds of PEG Reagents may be available by custom synthesis.